THE HAEMOFLAGELLATES 



213 



somes in general is based upon a plan fundamentally similar to 

 that described by Schaudinn in the case of his Avian parasite, 

 Trypanomorpha noduae. The development and ultimate constitution 

 of the nuclear apparatus in this type are as follows : 



The account may be commenced with the condition found in an 

 indifferent ookinete or individual which will become an indifferent (non- 

 sexual ) Trypanosome. Here a single, large compound or double nucleus 

 is present, consisting of an external portion and of an internal, central 



Development of an indifferent Try- 

 panosome from an ookinete of indif- 

 ferent character. (After Schaudinn.) 

 t.chr, trophonuclear chromosome ; 

 K.chr, kinetonuclear chromosome ; c, 

 centrosomic granule ; a.s, first axial 

 spindle; a.s 2 , a.s 3, second and third 

 spindle ; <, trophonucleus ; k, kineto- 

 nucleus ; k.c, kinetonuclear centro- 

 some ; t.c, trophonuclear centrosome ; 

 m, myonemes ; f.b, flagellar border of 

 undulating membrane (third axial 

 spindle) ; c3, its proximal centrosome. 



H 



portion (Fig. 10, A). The former has eight distinct, peripherally situated 

 chromosomes ; the latter also has eight separate chromosomes. In the 

 centre of all is a well-marked centrosomic granule (c). The first change 

 takes place by the inner body becoming amoeboid and giving up its 

 material to the outer, surrounding part (u). The result is that the eight 

 chromatic elements of the former become united, by the aid of the plasti- 

 noid basis present, with those of the latter, leaving the above-mentioned 

 grain in the middle. This granule divides in a dumb-bell-like manner, 

 producing a small axial spindle (c, ..)> around which the eight compound 

 chromosomes arrange themselves. These next split, and the halves pass 

 to either end, forming a diaster which is markedly heteropolar. The 



